The significance of reproductive properties and two modes in seed dispersal in the prostrate annual Chamaesyce maculata with multiple overlapping generations.

通过野外调查和室内试验，分析了多世代重叠的一年生匍匐花金龟生殖特性和两种种子传播方式的意义。获得了以下结果。1)6月出苗的植株从7月下旬开始有性生殖，此后至11月上旬营养生长和有性生殖同时发生，表现出由营养生长向有性生殖的转变。（2）斑叶甲在一年内最多重复3个世代。在第一和第二代产生的非休眠种子每年可获得多代，并明显导致每年生殖产量的增加。（3）可以认为，亲本与子代之间的竞争发生在生殖期的早期，而由后期种子产生的幼苗之间的竞争则发生在生殖期的后期， 关于我们 繁殖期的n发生在次年的出苗期。4）为了避免这种竞争，生殖期早季产生的种子自动分散（自播），导致种子分散远离亲本植株。5)繁殖后期产生的种子不是自动产生的，而是由采种蚁（myrmecochory）传播的。虽然有18种蚂蚁访问了斑叶蚁的植物，但只有两种杂食性蚂蚁，Tetramorium tsushimae和Pheidole nodus将种子带入巢穴。6）节蚁是典型的种子捕食者，其工蚁取食巢内携带的大部分种子，传播种子的效率明显较低，与收获蚁相似。（7）另一方面，工蜂将带入巢内的种子进行二次搬运，且从巢内搬运出的种子和留在巢内的种子的伤害率均极低。因此，可以认为，Tsushimae是一种上级的种子扩散剂，具有较高的种子扩散效率。少

The significance of reproductive properties and two modes of seed dispersal in the prostrate annual Chamaesyce maculata with multiple overlapping generations was analyzed in the field survey and laboratory experiments. The following results were obtained. 1)Plants that emerged in June commenced sexual reproduction from late July, and thereafter both vegetative growth and sexual reproduction occurred together until early November, the plants showing o switching from vegetative growth to sexual reproduction. 2)C.maculata could repeat a maximum of three overlapping generations within a year. Multiple generations per year were attained by non-dormant seeds produced in the first and second generaions and clearly resulted in an increased reproductive output per year. 3)It would be considered that competitions between parent plants and offspring plants occur in the early season of reproductive period, and competitions among seedlings that were derived from the seeds produced in the late seaso … More n of reproductive period occur in the emergence period in the next year. 4)In order to avoid such competitions, the seeds produced in the early season of reproductive period were automatically dispersed (autochory), resulting in seed dispersion far from parent plants. 5)the seeds produced in the late season of reproductive period were not automatically, but dispersed by seed-collecting ants (myrmecochory). Although 18 ant species visited plants of C.maculata, only two species of omnivorous ants, Tetramorium tsushimae and Pheidole nodus carried the seeds into their nests. 6)P.nodus was regarded as a typical seed predator, because P.nodus workers fed on most of the seeds carried in their nests, and the efficiency of seed dispersal by P.nodus was conspicuously low, similar as harvester ants. 7)On the other hand, workers of T.tsushimae carried out again about half number of the seeds that had carried into their nests, and the injury rates of both the seeds that carried out from their nests and those that remained in their nests were conspicuously low. Therefore, It would be considered that T.tsushimae is a superior seed disperser with high efficiency of seed dispersal for C.maculata. Less